1. Field of the Invention
One embodiment of the present invention relates to a light-emitting device and a method for driving the light-emitting device.
2. Description of the Related Art
Driving transistors used for most light-emitting devices such as flat panel displays typified by an EL display device are formed using silicon semiconductors such as amorphous silicon, single crystal silicon, and polycrystalline silicon provided over glass substrates.
In recent years, instead of the silicon semiconductor, a technique in which a metal oxide having semiconductor characteristics (an oxide semiconductor) is used for transistors has attracted attention. For example, a technique is disclosed in which a transistor is manufactured using zinc oxide or an In—Ga—Zn-based oxide as an oxide semiconductor and the transistor is used as a switching transistor or the like of a pixel of a display device (see Patent Document 1).